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Journal of Ocean University of China 2021年第2期20卷 340-348页

作者： DANG Tianxiang cao Yunyun xing Lei Key Laboratory of Marine Chemistry Theory and Technology Ministry of EducationOcean University of ChinaQingdao 266100China Laboratory for Marine Ecology and Environmental Science Qingdao National Laboratory for Marine Science and TechnologyQingdao 266071China

Stable carbon isotopic compositions of n-alkanes in surface sediments of the Bohai and North Yellow Seas were investigated to elucidate sources of sedimentary organic matter in these seas. The long-chain n-alkanes in surface sediments are predominantly long-chain C27, C29, and C31 types, with obvious odd carbon predominance. The δ13 C values of long-chain n-C27, n-C29, and n-C31 alkanes are-30.8% ± 0.5‰,-31.9% ± 0.6‰, and-32.1% ± 1.0‰, respectively, within the range of n-alkanes of C3 terrestrial higher plants. This suggests that sedimentary n-alkanes are derived mainly from terrestrial higher plants. Compound-specific carbon isotopic analysis of long-chain n-alkanes indicates that C3 terrestrial higher plants predominate(64%–79%), with angiosperms being the main contributors. The n-alkane δ13 C values indicate that mid-chain n-alkanes in sediments are derived mainly from aquatic emergent macrophytes, with significant petroleum pollution and bacterial degradation sources for short-chain n-alkanes.

关键词： biomarker carbon isotopes n-alkanes Bohai Sea North Yellow Sea

Numerical simulation of ice accretion in supercooled large droplet conditions

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Science China(Technological Sciences) 2019年第7期62卷 1191-1201页

作者： cao yi Hua XIN Miao School of Aeronautic Science and Engineering Beihang University

The simulated methods for ice accretion on two-dimensional airfoil surface are established completely under the Eulerian framework in supercooled large droplet(SLD) conditions. The two-dimensional code to solve the partial differential equations(PDEs) of droplet phase is derived to simulate the impingement characteristic of SLD. Also, several semi-empirical models which explain the droplet-wall interaction are compared and discussed to show respective features when simulating the splashing phenomenon. In particular, a new boundary condition for wall called penetrable wall for splashing droplet(PWSD) is proposed to deal with the impingement of SLD on solid surface, which efficiently improves the accuracy of simulation. Then the improved impingement characteristic of SLD is input into the extended mass and heat transfer model to simulate the ice growth on airfoil surface. The multistep advanced method is carried out to better match the physical phenomenon of ice growth. At last, the simulated results of critical parameters: local droplet collection efficiency and the height of ice growth are compared with the experimental data which verify the applicability of proposed models.

关键词： numerical simulation supercooled large droplet ice accretion penetrable wall for splashing droplet

Theoretical Studies on the Interactions of Cations with Diazine

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Chinese Journal of Structural Chemistry 2006年第11期25卷 1321-1330页

作者： CHEN xing WU Wen-Peng ZHANG Jing-Lai cao Ze-xing Institute of Fine Chemistry and Engineering Henan University Kaifeng 475001 China Department of Chemistry and State Key Laboratory for Physical Chemist~ of Solid Surfaces College of Chemistry and Chemical Engineering Xiamen University Xiamen 361005 China

Density functional theory and MP2 calculations have been used to determine the geometries, stabilities, binding energies, and dissociative properties of cation-diazine complexes M^n＋-C4H4N2 （M^n＋= Li^＋, B^＋, Al^＋, Be^2＋, Mg^2＋, Ca^2＋）. The calculated results indicate that most complexes are stable except the π complexes of Ca^2＋-pyridazine, Ca^2＋-pyrazine, Al^＋-pyrimidine and Al^＋-pyrimidine. The a complexes are generally much more stable than their π counterparts. Among the π complexes, the cation-pyrazine π complexes have slightly higher stability. The nature of the ion-molecule interactions has been discussed by the natural bond orbital analysis and frontier molecular orbital interactions. In these a complexes, there is stronger covalent interaction between B^＋ and diazine. In the selected π complexes, B^＋ and Be^2＋ have stronger covalent interaction with diazine, while the other cations mainly have electrostatic interaction with diazine.

关键词： DFT and MP2 calculations cation-diazine complexes cation-molecule interactions

Hybrid bimetallic cluster ZrO_(2)/Rh@N,S co-doped porous carbon nanosheets for efficient hydrogen evolution in acid electrolytes

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Tungsten 2024年第4期6卷 657-662页

作者： Xin-yi Zhang Igor V.Zatovsky Jun-Ming cao xing-Long Wu Faculty of Chemistry Northeast Normal UniversityChangchun130024China F.D.Ovcharenko Institute of Biocolloidal Chemistry NAS UkraineKiev03142Ukraine MOE Key Laboratory for UV Light-Emitting Materials and Technology Northeast Normal UniversityChangchun130024China

Acid hydrogen evolution reaction(HER)is a critical energy conversion process,which is significantly important in hydrogen energy manufacturing and storage[1].Although the performance of noble metal platinum(Pt)-based catalysts in acidic HER is well known,the challenges are high cost,limited reserves,poor stability,and susceptibility to toxic substances[2].Therefore,it is urgent to design and manufacture acidic HER catalysts with high reactivity,high stability,and low cost.

关键词： stability cluster porous

A spillover network analysis of the global crude oil market:Evidence from the post-financial crisis era

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Petroleum Science 2021年第4期18卷 1256-1269页

作者： Zhi-yi Ouyang Zheng Qin Hong cao Tian-Yu Xie xing-Yu Dai Qun-Wei Wang College of Economics and Management Nanjing University of Aeronautics and Astronautics29 Jiangjun AvenueNanjing211106China Research Center for Soft Energy Science Nanjing University of Aeronautics and AstronauticsNanjing211106China

The frequent occurrence of geopolitical crises in the post-financial crisis era is driving the rethinking behind whether the global crude oil market is still a highly connected"great pool".Using the spillover network model suggested by Baruník and Krehlík(2018),and the daily data of 31 global crude oil markets from 2009 to 2019,this study examines the return and volatility spillover effects and their timevarying behavior in six crude oil market segments at different *** findings indicate that heterogeneity exists in the co-movements between global crude oil markets in the post-financial crisis *** the medium term,both return and volatility spillover effects are not significant,which makes the diversified portfolio strategy *** in the Europe and Central Asian regions take the lead in return *** contrast,Asia-Pacific regional prices contribute the most in terms of volatility ***-term volatility spillovers increase sharply when confronted with oil-related events in the postfinancial crisis ***,policymakers should take effective measures to prevent any large-scale risk transmission in the long run.

关键词： Oil price Network analysis Spillover effect Multiscale analysis Baruník and Krehlík model

Asymmetric interfacial engineering regulated charge distribution on Ru/Ni-N-C sites for efficient hydrogen evolution reaction in alkaline and seawater electrolytes

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Science China Chemistry 2025年

作者： Rui Yu Xi cao Chengyang Zhu Qingqing Chen Ziyi Yan Binbin Jiang Junjie Mao Xianwen Wei Key Laboratory of Electrochemical Clean Energy of Anhui Higher Education Institutes College of Chemistry and Materials ScienceAnhui Normal University Anhui Provincial Key Laboratory of Advanced Catalysis and Energy Materials School of Chemistry and Chemical Engineering Anqing Normal University School of Chemistry and Chemical Engineering Anhui University of Technology

Developing highly efficient and cost-effective electrocatalysts for hydrogen evolution reaction（HER） is grandly challenging in alkaline and alkaline seawater electrolytes. Herein, the asymmetric interfacial active sites with Ru nanoparticles and Ni single atoms in Ru/Ni-N-C were designed through a solvothermal-pyrolysis process. Constructing highly asymmetric interfacial active sites with a strong electron delocalization effect significantly improves HER kinetics. As expected, Ru/Ni-N-C requires low overpotentials with around 20 mV at 10 mA cm-2and robust durability over 48 h in alkaline and alkaline seawater *** at 200 mA cm-2, the overpotentials are close to 100 mV in both above electrolytes for Ru/Ni-N-C. Density function theory calculation results suggest that the asymmetric interface between Ru nanoparticle and Ni-N-C could accelerate the dissociation of water molecules and modulate the hydrogen species, consequently improving the HER performances. This work opens a unique approach for constructing advanced materials for energy conversion.

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Final size of network epidemic models: properties and connections

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Science China(Information Sciences) 2021年第7期64卷 244-246页

作者： yi WANG Jinde cao School of Mathematics Southeast University School of Mathematics and Physics China University of Geosciences Jiangsu Provincial Key Laboratory of Networked Collective Intelligence Southeast University

Dear editor,The classical final size relation of the standard susceptible-infected-recovered (SIR) epidemic model is based on homogeneous-mixing population [1, 2]. Recent results have demonstrated the generality of th... 详细信息

关键词： Epidemic models Complex networks Final size Degree distribution Control effort

A fuzzy quantification approach of uncertainties in an extreme wave height modeling

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Acta Oceanologica Sinica 2015年第3期34卷 90-98页

作者： ZHANG yi cao yingyi Division of Infrastructure Systems and Maritime Studies School of Civil and Environmental EngineeringNanyang Technological University College of Preschool Education Zibo Normal College

A non-traditional fuzzy quantification method is presented in the modeling of an extreme significant wave height. First, a set of parametric models are selected to fit time series data for the significant wave height and the extrapolation for extremes are obtained based on high quantile estimations. The quality of these results is compared and discussed. Then, the proposed fuzzy model, which combines Poisson process and gener-alized Pareto distribution （GPD） model, is applied to characterizing the wave extremes in the time series data. The estimations for a long-term return value are considered as time-varying as a threshold is regarded as non-stationary. The estimated intervals coupled with the fuzzy theory are then introduced to construct the probability bounds for the return values. This nontraditional model is analyzed in comparison with the traditional model in the degree of conservatism for the long-term estimate. The impact on the fuzzy bounds of extreme estimations from the non stationary effect in the proposed model is also investigated.

关键词： offshore engineering extreme value distribution wave height peak over threshold fuzzy set Pareto distribution

ON THE COMPLEX OSCILLATION OF HIGHER ORDER LINEAR DIFFERENTIAL EQUATIONS WITH MEROMORPHIC COEFFICIENTS

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Journal of Systems Science & Complexity 2007年第1期20卷 135-148页

作者： Tingbin cao Hongxun yi Department of Mathematics Shandong University Jinan 250100 China

In this paper, we investigate the complex oscillation of higher order homogenous and non- homogeneous linear differential equations with meromorphic coefficients of iterated order, and obtain some results which improv... 详细信息

关键词： Exponent iterated convergence iterated order linear differential equation meromorphic function.

Homogenization of a Nonlinear Degenerate Parabolic Differential Equation

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Acta Mathematica Sinica,English Series 2013年第7期29卷 1429-1436页

作者： Hai Tao cao xing Ye YUE Department of Mathematics and Physics Changzhou Campus Hohai University Department of Mathematics Soochow University

This paper is devoted to the homogenization of a nonlinear degenerate parabolic problemwith Dirichlet boundary condition. Here the operator D（y, s, △s） is periodic in y and degenerated in △s. In the paper, under the two-scale convergence theory, we obtain the limit equation as ∈ → 0 and also prove the corrector results of △u^∈ to strong convergence.

关键词： Nonlinear degenerate parabolic equation homogenization two-scale convergence